Compensation of angular indexing error for precision turntable

Authors：WANG Fu quan; WANG Jue; XIE Zhi jiang; LIU Feng lin

Source：光学精密工程, 2017, 25(8).

DOI：10.3788/OPE.20172508.2165

• precision turntable
• angular indexing error
• sparse decomposition
• error compensation

A compensation method for angular indexing error was introduced based on sparse decomposition to correct the angular indexing error caused by the eccentric and tilt of circular gratings installment in a precision turntable.First, the effect of circular grating installed eccentric and tilt on the angular indexing error was analyzed.Next, according to the characteristics of different orders of error in measuring error of circular grating angle, a compensation model of angular indexing error was built based on the sparse decomposition theory and the harmonic analysis to compensate the angular indexing error of the turntable.Finally, a test platform was established, and the effectiveness of the proposed method was verified to compensate the angular indexing error of a precision turntable.The experimental results show that the proposed method can increase 2 orders of magnitude of the angular indexing accuracy.The maximum value of angular indexing error can be reduced to 0.64" from 90.85" through proposed error compensation method.After error compensation with the method, the accuracy of angle positioning can be remarkably improved, meeting the high-accuracy testing requirements of angular displacement of a precision turntable.

• Institution
  重庆大学